1. Field of the Invention
This invention relates to photosensitive elements and more particularly to photosensitive elements that employ a reduced quantity of silver halide. Even more particularly, this invention relates to low silver photographic elements that employ photosensitive polymers within the image producing system and produce positive images using a wash-off developing technique.
2. Description of the Prior Art
There are a host of prior art applications relating to wash-off elements, some of which are also related to either low silver or no silver bearing elements. There are also other elements which are reported to contain developed or fogged silver which is employed to improve the image. These prior art references are fully described in U.S. Pat. No. 4,923,389, the substance of which is incorporated herein by reference. This reference teaches a process of forming a negative-working low silver contact film which is developed by wash-off techniques. In the element disclosed in this reference, a dual-layered coating is provided on a support. One layer, coated nearest the support, contains silver halide grains dispersed in a photopolymeric system which includes binder, polymer and initiator. The second layer, or abrasion layer, contains an organic binder and a tanning developer. After an image-wise exposure, the element is developed by immersion into an alkaline solution which causes the tanning developer to migrate image-wise into the silver halide-containing layer and crosslink the polymer contained therein. A negative image is then obtained by washing out the unexposed areas with water.
Neither the aforementioned patent nor any of the prior art elements known to the inventor describe a method for achieving a direct positive image using a low silver element in combination with a photopolymer system and wash-out development.